US20170363004A1

Movatterモバイル変換

Info

Publication number: US20170363004A1
Application number: US15/187,149
Authority: US
Inventors: Jinquan Xu
Original assignee: United Technologies Corp
Current assignee: RTX Corp
Priority date: 2016-06-20
Filing date: 2016-06-20
Publication date: 2017-12-21
Also published as: US10458331B2; EP3260780A1; EP3260780B1

Abstract

Fuel injectors for gas turbine engines are provided herein. The fuel injectors include a nozzle configured to dispense fuel into a combustor of a gas turbine engine, a fuel conduit fluidly connecting a fuel source to the nozzle, and a heat pipe having a vaporization section and a condensation section, wherein the vaporization section is in thermal communication with the nozzle and the condensation section is in thermal communication with a cooling source of the gas turbine engine.

Description

BACKGROUND

The subject matter disclosed herein generally relates to components for combustors in gas turbine engines and, more particularly, to improved cooling for components of combustors of gas turbine engines.

Gas turbine engines, such as those that power modern commercial and military aircraft, include a compressor section to pressurize a supply of air, a combustor section to burn a hydrocarbon fuel in the presence of the pressurized air, and a turbine section to extract energy from the resultant combustion gases and generate thrust. The combustor section generally includes a plurality of circumferentially distributed fuel injectors that project toward a combustion chamber to supply fuel to be mixed and burned with the pressurized air. Gas turbine engines typically include a plurality of centralized staging valves in combination with one or more fuel supply manifolds that deliver fuel to the fuel injectors.

Each fuel injector typically has an inlet fitting connected to the manifold at the base, a conduit connected to the base fitting, and a nozzle connected to the conduit to spray the fuel into the combustion chamber. Appropriate valves or flow dividers are provided to direct and control the flow of fuel through the nozzle.

A combustor may include pilot and main fuel injectors. Generally, the main fuel injectors are for normal and high power situations, while the pilot fuel injectors are used for start operation or for emission control. The main or pilot fuel injectors have relatively small openings in the nozzles and small fuel passages in the conduits that may be prone to coke formation due to high fuel temperature. Coke formation may result in narrowed fuel openings in the nozzles, uneven fuel burn and increased maintenance requirements. Further, coke formation may form in the fuel conduit of the fuel injector, break off in fragments and ultimately obstruct fuel injector nozzle tip openings.

Conventional fuel injector designs typically utilize heat shields around the fuel injector conduit to provide a passive insulated, static, air gap and reduce the heat transfer rate within a diffuser case module to the fuel.

SUMMARY

According to one embodiment, a fuel injector for a gas turbine engine is provided. The fuel injector includes a nozzle configured to dispense fuel into a combustor of a gas turbine engine, a fuel conduit fluidly connecting a fuel source to the nozzle, and a heat pipe having a vaporization section and a condensation section, wherein the vaporization section is in thermal communication with the nozzle and the condensation section is in thermal communication with a cooling source of the gas turbine engine.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the cooling source is at least one of the fuel of the fuel injector or compressed air.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the vaporization section of the heat pipe is wrapped around the nozzle.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that at least a portion of the heat pipe passes through a wall of a portion of the fuel injector.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the heat pipe is integrally formed with at least one of the nozzle and the fuel conduit.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the heat pipe is one of a thermosiphon, a capillary-driven heat pipe, an annular heat pipe, a vapor chamber, a gas-loaded heat pipe, a loop heat pipe, a capillary pumped loop heat pipe, a pulsating heat pipe, a micro heat pipe, or a miniature heat pipe.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the nozzle and fuel conduit are components of an axially staged fuel injector.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the nozzle and fuel conduit are components of a radially staged fuel injector.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that at least a portion of the fuel injector is additively manufactured and the heat pipe is formed by the additive manufacturing process within the fuel injector.

In addition to one or more of the features described above, or as an alternative, further embodiments of the fuel injector may include that the heat pipe is a pulsating heat pipe.

According to another embodiment, a gas turbine engine is provided. The gas turbine engine includes a combustor section having a plurality of components and a heat pipe configured with at least one of the plurality of components of the combustor section, the heat pipe having a vaporization section and a condensation section, wherein the vaporization section of the heat pipe is in thermal communication with the at least one component and the condensation section is in thermal communication with a cooling source.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the at least one component is a first fuel injector having a nozzle and a fuel conduit fluidly connecting a fuel source to the nozzle, wherein the vaporization section is in thermal communication with the nozzle and the condensation section is in thermal communication with the cooling source.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the vaporization section of the heat pipe is wrapped around the nozzle.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the nozzle and fuel conduit are components of an axially staged fuel injector.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the first fuel injector is an axially staged fuel injector of the gas turbine engine.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include a second fuel injector that is a radially staged fuel injector of the gas turbine engine.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the second fuel injector includes a second nozzle configured to dispense fuel into the combustor and a second fuel conduit fluidly connecting a second fluid source to the second nozzle, the gas turbine engine further comprising a second heat pipe having a vaporization section and a condensation section, wherein the vaporization section of the second heat pipe is in thermal communication with the nozzle of the second fuel injector and the condensation section of the second heat pipe is in thermal communication with a second cooling source.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that at least one of the first and second fluid sources are the same fluid source or the first and second cooling sources are the same cooling source.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the heat pipe is integrally formed with the at least one component of the combustor.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the heat pipe is one of a thermosiphon, a capillary-driven heat pipe, an annular heat pipe, a vapor chamber, a gas-loaded heat pipe, a loop heat pipe, a capillary pumped loop heat pipe, a pulsating heat pipe, a micro heat pipe, or a miniature heat pipe.

In addition to one or more of the features described above, or as an alternative, further embodiments of the gas turbine engine may include that the component of the combustor is additively manufactured and the heat pipe is formed by the additive manufacturing process within the component.

Technical effects of embodiments of the present disclosure include fuel injectors and other components of gas turbine engines having improved cooling. Further technical effects include fuel injectors having heat pipes configured therewith to provide improved cooling to a component of a gas turbine engine (e.g., a nozzle of a fuel injector).

The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter is particularly pointed out and distinctly claimed at the conclusion of the specification. The foregoing and other features, and advantages of the present disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1A is a schematic cross-sectional illustration of a gas turbine engine that may employ various embodiments disclosed herein;

FIG. 1B is a schematic illustration of a combustor section of a gas turbine engine that may employ various embodiments disclosed herein;

FIG. 2 is a schematic illustration of a fuel injector incorporating a heat pipe in accordance with an embodiment of the present disclosure;

FIG. 3A is a schematic illustration of an alternative configuration of a heat pipe installed with a fuel injector in accordance with an embodiment of the present disclosure;

FIG. 3B is a schematic illustration of an alternative configuration of a heat pipe installed with a fuel injector in accordance with an embodiment of the present disclosure; and

FIG. 4 is a schematic illustration of an alternative configuration of heat pipes installed within fuel injectors of a radially staged combustor in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

As shown and described herein, various features of the disclosure will be presented. Various embodiments may have the same or similar features and thus the same or similar features may be labeled with the same reference numeral, but preceded by a different first number indicating the figure to which the feature is shown. Thus, for example, element “a” that is shown in FIG. X may be labeled “Xa” and a similar feature in FIG. Z may be labeled “Za.” Although similar reference numbers may be used in a generic sense, various embodiments will be described and various features may include changes, alterations, modifications, etc. as will be appreciated by those of skill in the art, whether explicitly described or otherwise would be appreciated by those of skill in the art.

FIG. 1A schematically illustrates agas turbine engine20. The exemplarygas turbine engine20 is a two-spool turbofan engine that generally incorporates afan section22, acompressor section24, a combustor section26, and aturbine section28. Alternative engines might include an augmenter section (not shown) among other systems for features. Thefan section22 drives air along a bypass flow path B, while thecompressor section24 drives air along a core flow path C for compression and communication into the combustor section26. Hot combustion gases generated in the combustor section26 are expanded through theturbine section28. Although depicted as a turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to turbofan engines and these teachings could extend to other types of engines, including but not limited to, three-spool engine architectures.

Thegas turbine engine20 generally includes alow speed spool30 and ahigh speed spool32 mounted for rotation about an engine centerline longitudinal axis A. Thelow speed spool30 and thehigh speed spool32 may be mounted relative to an enginestatic structure33 viaseveral bearing systems31. It should be understood that other bearingsystems31 may alternatively or additionally be provided.

Thelow speed spool30 generally includes aninner shaft34 that interconnects afan36, alow pressure compressor38 and a low pressure turbine39. Theinner shaft34 can be connected to thefan36 through a gearedarchitecture45 to drive thefan36 at a lower speed than thelow speed spool30. Thehigh speed spool32 includes anouter shaft35 that interconnects ahigh pressure compressor37 and ahigh pressure turbine40. In this embodiment, theinner shaft34 and theouter shaft35 are supported at various axial locations by bearingsystems31 positioned within the enginestatic structure33.

Acombustor42 is arranged between thehigh pressure compressor37 and thehigh pressure turbine40. Amid-turbine frame44 may be arranged generally between thehigh pressure turbine40 and the low pressure turbine39. Themid-turbine frame44 can support one ormore bearing systems31 of theturbine section28. Themid-turbine frame44 may include one ormore airfoils46 that extend within the core flow path C.

Theinner shaft34 and theouter shaft35 are concentric and rotate via the bearingsystems31 about the engine centerline longitudinal axis A, which is co-linear with their longitudinal axes. The core airflow is compressed by thelow pressure compressor38 and thehigh pressure compressor37, is mixed with fuel and burned in thecombustor42, and is then expanded over thehigh pressure turbine40 and the low pressure turbine39. Thehigh pressure turbine40 and the low pressure turbine39 rotationally drive the respectivehigh speed spool32 and thelow speed spool30 in response to the expansion.

The pressure ratio of the low pressure turbine39 can be pressure measured prior to the inlet of the low pressure turbine39 as related to the pressure at the outlet of the low pressure turbine39 and prior to an exhaust nozzle of thegas turbine engine20. In one non-limiting embodiment, the bypass ratio of thegas turbine engine20 is greater than about ten (10:1), the fan diameter is significantly larger than that of thelow pressure compressor38, and the low pressure turbine39 has a pressure ratio that is greater than about five (5:1). It should be understood, however, that the above parameters are only examples of one embodiment of a geared architecture engine and that the present disclosure is applicable to other gas turbine engines, including direct drive turbofans.

In this embodiment of the examplegas turbine engine20, a significant amount of thrust is provided by the bypass flow path B due to the high bypass ratio. Thefan section22 of thegas turbine engine20 is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet (10,668 meter). This flight condition, with thegas turbine engine20 at its best fuel consumption, is also known as bucket cruise Thrust Specific Fuel Consumption (TSFC). TSFC is an industry standard parameter of fuel consumption per unit of thrust.

Fan Pressure Ratio is the pressure ratio across a blade of thefan section22 without the use of a Fan Exit Guide Vane system. The low Fan Pressure Ratio according to one non-limiting embodiment of the examplegas turbine engine20 is less than 1.45. Low Corrected Fan Tip Speed is the actual fan tip speed divided by an industry standard temperature correction of [(T_ram° R)/(518.7° R)]^0.5, where T_ramrepresents the ambient temperature in degrees Rankine. The Low Corrected Fan Tip Speed according to one non-limiting embodiment of the examplegas turbine engine20 is less than about 1150 feet per second (fps) (351 meters per second (m/s)).

Each of thecompressor section24 and theturbine section28 may include alternating rows of rotor assemblies and vane assemblies (shown schematically) that carry airfoils that extend into the core flow path C. For example, the rotor assemblies can carry a plurality ofrotating blades25, while each vane assembly can carry a plurality ofvanes27 that extend into the core flow path C. Theblades25 of the rotor assemblies create or extract energy (in the form of pressure) from the core airflow that is communicated through thegas turbine engine20 along the core flow path C. Thevanes27 of the vane assemblies direct the core airflow to theblades25 to either add or extract energy.

With reference toFIG. 1B, an enlarged schematic illustration of thecombustor42 is shown. Thecombustor42 can be annular and generally includes anouter wall102, aninner wall104 and adiffuser case module106. Theouter wall102 and theinner wall104 are spaced apart radially with respect to axis A and such that acombustion chamber108 is generally defined there between. Thecombustion chamber108 is generally annular in shape. Theouter wall102 is spaced radially inward from a diffuserouter case110 of thediffuser case module106, with an annularouter plenum112 being defined there between. Theinner wall104 is spaced radially outward from a diffuserinner case116 of thediffuser case module106 to define an annularinner plenum116. It should be understood that although a particular combustor is illustrated, other combustor types with various combustor wall and case arrangements will also benefit here from. For instance, the diffuserouter case110 maybe an integral part of anengine case structure118.

Furthermore, although shown and described with respect to an aircraft engine, those of skill in the art will appreciate that embodiments provided herein can be employed within land-based or sea-based gas turbine engines and/or so industrial gas turbines (IGT). Furthermore, combustors as provided herein can be annular combustors, can combustors, or other types of combustors as known in the art. Further, in some embodiments, such as in industrial gas turbines, as known, water may be injected into the combustion chamber and used for emission control. Such water and/or associated water supply can be used as a cooling source for the heat pipes as described herein.

Each

combustor wall

102,104 generally includes a

respective support shell

120,122, respectively, that supports one or

more liners

124,126, respectively, mounted to a hot side of the

respective support shell

120,122. The

liners

124,126 directly define thecombustion chamber108 that contains the flow of combustion products for driving theturbine section28. The

liners

124,126 can be comprised of a plurality of Impingement Film Float (IFF) panels orientated in a generally rectilinear liner array. Each panel can be manufactured of, for example, a nickel based super alloy, ceramic, or other temperature resistant material. In non-limiting embodiments, the array of panels of the liners can include a plurality of forward liner panels and a plurality of aft liner panels that line the hot side of theouter shell120 and a plurality of forward liner panels and a plurality of aft liner panels that line the hot side of theinner shell122.

Thecombustor42 also includes aforward assembly128 immediately downstream of thecompressor section24 to guide compressed airflow C therefrom. Theforward assembly128 generally includes anannular hood130, abulkhead assembly132, and a plurality of swirlers134 (one shown) spaced circumferentially about engine axis A.

Theannular hood130 extends radially between, and in the non-limiting embodiment ofFIG. 1B, is secured to, the forward most ends of the

walls

102,104. A plurality of circumferentially distributedhood ports136 accommodate a respective plurality offirst fuel injectors138 as well as direct compressed air C into the forward end of thecombustion chamber108 through the associatedswirler134. Eachfirst fuel injector138, such as a primary fuel injector, can be secured to thediffuser case module106 to project through one of thehood ports136 and therespective swirler134. It should be appreciated that various architectures of theforward assembly128 can also benefit here from.

Eachswirler134, as shown inFIG. 1B, is circumferentially aligned with arespective hood port136 to project through thebulkhead assembly132. Thebulkhead assembly132 includes abulkhead support shell140 secured to the

walls

102,104, and a plurality of circumferentially distributedbulkhead heat shields142 secured to thebulkhead support shell140 around eachswirler134.

Theforward assembly128 and

walls

102,104 are configured to introduce core combustion air C into the forward end of thecombustion chamber108 while the remainder enters from the annularouter plenum112 and the annularinner plenum116. The plurality of first fuel injectors (or main fuel injector)138 andrespective swirlers134 facilitate the generation of a blended fuel-air mixture that supports combustion in thecombustion chamber108.

Additionally, thecombustor42 can be configured with one or more second fuel injectors144 (e.g., axially staged, pilot fuel injectors). Thesecond fuel injectors144 can be configured or structured similar to the first fuel injectors138 (e.g., including swirlers, shells, supports, etc.). A difference between thesecond fuel injectors144 and thefirst fuel injectors138 may be the direction of injection of fuel into thecombustion chamber108. Thefirst fuel injectors138 inject fuel in a first direction (e.g., substantially axially along the axis A) whereas thesecond fuel injectors144 inject fuel in a second direction substantially parallel to or different from the first direction. In some embodiments, the second fuel injectors can be oriented with an angle with respect to the first fuel injector(s).

As noted previously, various fuel injection systems in gas turbine engines can be subject to coking in the fuel injectors (e.g., first andsecond fuel injectors138,144), and particularly in the fuel nozzles. Coking occurs when a given fuel is heated above its critical coking temperature. Further, within staged fuel injectors, inactive or non-flowing fuel resting in nozzles or fuel conduits are vulnerable to coking. Active cooling to the nozzles and fuel conduits of the staged fuel injectors is one method to address this challenge. One example of active cooling, as presented herein, includes a heat pipe configured within, in proximity of, or wrapped around the fuel nozzle and/or fuel conduit. For example, the heat pipe, an enclosed device configured to transport heat from a vaporization section to a condensation section through cyclical evaporation and condensation of a working medium sealed in the device, can dramatically enhance cooling effectiveness within fuel nozzles or fuel conduits. That is, in accordance with various embodiments of the present disclosure, heat pipe enhanced fuel nozzle and fuel conduit cooling is provided.

For example, turning toFIG. 2, a component of a combustion section, e.g., a fuel injector, having an embedded heat pipe cooling configuration is schematically shown. As shown, afuel injector238 includes afuel conduit246 that is configured to directfuel248 from afuel source249 to afuel nozzle250 that injects the fuel into a combustion chamber, as described above. Thefuel248 can be relatively cold when sourced from thefuel source249 butfuel248 can become hot while flowing through thefuel conduit246 toward thefuel nozzle250 as thefuel injector238 is immersed in hot compressed core air. In addition, thefuel nozzle250, particularly the fuel nozzle of a pilot fuel injector, is exposed to the high temperatures within the combustion chamber and thefuel248 can be heated while still within a portion of thefuel injector238. As such, close to thefuel nozzle250

fuel

248 can be heated above the critical coking temperature of thefuel248. Accordingly, thefuel injector238 can include a relativelyhot section256 and a relativelycool section258.

In order to prevent or to mitigate the high temperatures, and thus minimize or eliminate coking at thenozzle250, aheat pipe260 can be provided in, on, or around at least a portion of thefuel injector238. For example, as shown inFIG. 2, theheat pipe260 is embedded within thefuel injector238 and extends from thecool section258 into thehot section256 and to acooling source252. Theheat pipe260 can thus facilitate cooling of thehot section256 of thefuel injector238 to minimize or prevent coking at thenozzle250. Theheat pipe260 can be an annular or cylindrically-shaped heat pipe structure, as shown in cross-section inFIG. 2, or in other embodiments, a number of pulsating heat pipes (also referred to as loop-type heat pipes) or sheet-shaped miniature heat pipes can be configured extending from thehot section256 to thecold section258 to thecooling source252, or other heat pipe configurations such as a thermosiphon heat pipe, a capillary-driven heat pipe, a vapor chamber heat pipe, a gas-loaded heat pipe, a capillary pumped loop heat pipe, a micro heat pipe, or a miniature heat pipe are possible as known in the art.

Theheat pipe260 includes avaporization section262 and acondensation section264. Thevaporization section262 is in thermal communication with thehot section256 of the fuel injector238 (e.g.,fuel conduit246 and nozzle250) and thecondensation section264 of theheat pipe260 is in thermal communication with a cooling source252 (e.g., a cooling air source, bleed cooling air, a fuel source, a cool section of the fuel conduit, water, etc.). That is, in some embodiments, thecooling source252 and thefuel source249 can be a single unit (or the same unit/source) or thecooling source252 can befuel248 within thefuel conduit246 that is relatively cool. In other embodiments, thecooling source252 can be separate from the fuel source249 (e.g., a bleed cooling air source or air supplied for fuel mixing or combustion). Accordingly, in accordance with some embodiments, thecondensation section264 is at least partially (thermally) exposed within thefuel injector238 and in thermal contact with a running, relatively cool fuel upstream of thehot section256. Thevaporization section262 is in thermal contact with fuel and/or gases that are at or near thehot section256 such as thenozzle250. Such a configuration can take advantage of a relatively cool temperature of thefuel248 and transfer thermal energy into thefuel248 from thecondensation section264 while a workingmedium261 in theheat pipe260 condenses (evaporate comes from the vaporization section262). The condensed workingmedium261 can then flow to thevaporization section262 to receive thermal energy (heat) at thehot section256 such as thenozzle250. The condensed workingmedium261 will then vaporize and flow back to thecondensation section264.

Although described above with respect to a heat pipe configured within a fuel injector of a combustor section of a gas turbine engine, those of skill in the art will appreciate that heat pipes can be installed into, on, or otherwise configured with various other components of a combustor section of a gas turbine engine to facilitate cooling. For example, in some embodiments of the present disclosure, heat pipes can be configured within combustor liners, bulk head structures of the combustor, heat shields, swirlers, hoods, support shells, etc. Accordingly, the present disclosure is not intended to be limited to heat pipes within fuel injectors, but rather such configurations are provided for illustrative and explanatory purposes.

Turning now toFIG. 3A, an alternative configuration of a cooled fuel injector in accordance with an embodiment of the present disclosure is shown. InFIG. 3A, afuel injector344ais shown and is configured as an axially staged fuel injector (e.g., as described above). Thefuel injector344aincludes a similar configuration to that shown and described above and thus certain features will not be shown or described in detail for simplicity. The primary difference between the configuration ofFIG. 2 and the configuration ofFIG. 3A is that aheat pipe360a, having working medium361a, inFIG. 3A is wrapped around an exterior of thefuel injector344a(as compared to being embedded within the fuel injector/fuel conduit) for retrofitting.

As shown, theheat pipe360aincludes avaporization section362athat is wrapped around or embedded within anozzle350aof thefuel injector344a. Further, as shown, acondensation section364aof theheat pipe360ais configured to extend along thefuel injector344a(e.g., to acooling source352a). In some embodiments, thecondensation section364acan be configured to pass through an aperture in the side of thefuel injector344asuch that thecondensation section364aextends into an interior fuel conduit of thefuel injector344a. In some embodiments, thecondensation section364acan be extended into acooling source352a(e.g., fuel source of the fuel injector). In such embodiments, thecondensation section364acan enable direct thermal contact between theheat pipe360aand a cool fuel within thefuel injector344a. In other embodiments, such as that shown inFIG. 3A, thecondensation section364amay extend along an exterior surface of thefuel injector344ato thecooling source352a. In another embodiment, the heat pipe is a pulsating heat pipe.

Turning now toFIG. 3B, an alternative configuration of a heat pipe installed with a fuel injector in accordance with the present disclosure is shown. In the embodiment ofFIG. 3B, thefuel injector344bis similar to that shown inFIG. 3A. However, theheat pipe360bhas a different, alternative structure. As shown, theheat pipe360bhas an annular structure that is wrapped around or embedded within thenozzle350bof thefuel injector344b. In alternative configurations, the structure of the heat pipe can be embedded into or additively manufactured with the nozzle and/or the fuel injector. As shown, theheat pipe360bincludes avaporization section362bthat is in thermal contact and configured around anozzle350bas a ring or annular structure and acondensation section364bof theheat pipe360bis configured to extend along thefuel injector344b(or into thefuel injector344bas described above) to acooling source352b. Further, in some embodiments, the structure can extend from thenozzle350btoward or into a fuel conduit (e.g., a cooling source) of thefuel injector344b(or aseparate cooling source352b). That is, in some embodiments, the annular structure can form a cylinder that extends from the nozzle toward the fuel conduit of the fuel injector.

Turning now toFIG. 4, a two fuel injector system (e.g., a radially staged combustor) having embedded heat pipe cooling configurations is schematically shown. As shown, afirst fuel injector438aincludes afirst fuel conduit446athat is configured to direct afirst fuel448afrom afirst fuel source449ato afirst fuel nozzle450athat injects the fuel into acombustion chamber408, as described above. As shown, asecond fuel injector438bincludes asecond fuel conduit446bthat is configured to direct asecond fuel448bfrom asecond fuel source449bto asecond fuel nozzle450bthat injects the fuel into thecombustion chamber408 at a radially different location than thefirst fuel nozzle450a. In some embodiments, as will be appreciated by those of skill in the art, the first and

second fuel sources

449a,449bcan be the same fuel source with fuel that is supplied along the first and

second fuel conduits

446a,446b.

Similar to the embodiments described above, in order to prevent or to mitigate high temperatures and thus minimize or eliminate coking at the

nozzles

450a,450b, first and

second heat pipes

460a,460bcan be provided in, on, or around a portion of

respective fuel injectors

438a,438b. For example, as shown inFIG. 4, afirst heat pipe460ais embedded within or wrapped around thefirst fuel conduit446aand extends to thefirst nozzle450a. Similarly, asecond heat pipe460bis embedded within or wrapped around thesecond fuel conduit446band extends to thesecond nozzle450b. The first and

second heat pipes

460a,460bcan thus facilitate cooling to

respective fuel injectors

438a,438bto minimize or prevent coking at the

nozzles

450a,450bthereof. The

heat pipes

460a,460bcan be an annular or cylindrical heat pipe structures, pulsating heat pipes, sheet-shaped heat pipes, or can be configured in other shapes, sizes, geometries, etc. as known in the art. The

heat pipes

460a,460bcan function as describe above and be thermally in communication with

respective cooling sources

452a,452b(which in some embodiments is the same cooling source; and in some embodiments may be the

fuel sources

449a,449b).

As used herein, the heat pipes in accordance with various embodiments may include, but are not limited to, two-phase closed thermosiphons, capillary-driven heat pipes, annular heat pipes, vapor chambers, gas-loaded heat pipes, loop heat pipes, capillary pumped loop heat pipes, pulsating heat pipes, micro or miniature heat pipes, inverted meniscus heat pipes, or other types of heat pipes or thermal transfer devices as known in the art. Further, working media may include, but is not limited to, helium, nitrogen, ammonia, acetone, methanol, fluorocarbon liquids, ethanol, water, toluene, mercury, sodium, lithium, silver, combinations thereof, etc. Those of skill in the art will appreciate that the material used to form the heat pipe may be selected based on thermal requirements, weight requirements, working medium requirements, or other requirements or needs, and the material used to form the heat pipes is not to be limited. Further, various heat pipes as employed herein can include interior structures including, but not limited to, ribs, lattice structures, fins, etc. that can be configured within the heat pipes that may be configured to provide structural support or integrity to the heat pipes or augment thermal transfer within the heat pipes. For example, in some embodiments, the heat pipes can be configured with rib structures, lattice structures, or other structures that are configured to connect inner and outer walls of the heat pipes.

Although described above with respect to the heat pipe being exposed to cool fuel within the fuel conduit, those of skill in the art will appreciate that alternative cooling means can be used without departing from the scope of the present disclosure. Those of skill in the art will appreciate that the heat pipes can be exposed to any cooling source. For example, in some embodiments, the condensation section of the heat pipe can be exposed to cooling gases (e.g., cooling air, swirler air, water, etc.) that is used for cooling within a gas turbine engine. Further, other cooling sources can be used as will be appreciated by those of skill in the art. Advantageously, embodiments provided herein are configured to take advantage of already existing relatively cool mediums to enable condensation of a working fluid within a heat pipe that is in thermal contact or communication with a nozzle of a fuel injector.

Advantageously, various heat pipes as provided herein can be installed onto existing fuel nozzles or can be formed in or with a nozzle during manufacturing of the nozzle. For example, a heat pipe can be wrapped around the exterior of the nozzle (e.g.,FIGS. 3A-3B) and thus be applied to existing configurations. Alternatively, a heat pipe can be embedded within or manufactured with the formation of the fuel injector (nozzle, fuel conduit, etc.). In some embodiments, the fuel injector can be partially or entirely additively manufactured such that the heat pipe is integrally formed within and part of the structure of the fuel injector.

Advantageously, embodiments described herein provide a cooled fuel injector nozzle such that coking can be minimized or prevented. Further, advantageously, heat pipe cooling as provided herein may substantially isothermalize the nozzle tip portion of a fuel injector and thus minimize hot spots. Moreover, advantageously, heat dissipated by the heat pipe can be directed toward relatively cool fuel within a fuel conduit and thus pre-heat the fuel for combustion. Further, advantageously, by selecting the working medium or heat pipe configuration, the tip temperature of the nozzle can be controlled in a narrow band to prevent coke forming.

While the present disclosure has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the present disclosure is not limited to such disclosed embodiments. Rather, the present disclosure can be modified to incorporate any number of variations, alterations, substitutions, combinations, sub-combinations, or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the present disclosure. Additionally, while various embodiments of the present disclosure have been described, it is to be understood that aspects of the present disclosure may include only some of the described embodiments.

For example, although shown with a single heat pipe (e.g.,FIGS. 2-3), those of skill in the art will appreciate that fuel injectors can be configured with multiple heat pipes, as described herein, such that a desired heating/cooling profile can be achieved at the nozzle of the fuel injectors. Further, various configurations can take advantage of both liquid (e.g., fuel, water) and gas (e.g., cooling air) cooling for the heat pipes, as desired. Moreover, although shown with specific heat pipe configurations with specific fuel injector configurations, those of skill in the art will appreciate that such configurations are not to be limiting. For example, an axially staged combustor can include a heat pipe configuration(s) similar to that show inFIG. 4.

Further, those of skill in the art will appreciate that the heat pipes shown and described herein can be installed in various types of combustors or components thereof. For example, in some embodiments, heat pipes of the present disclosure can be installed into or formed with fuel injectors of radially staged combustors or within fuel injectors of can combustors. Additionally, although show with respect to fuel injectors, those of skill in the art will appreciate that heat pipes of the present disclosure can be installed with, on, or in various other components of combustors or combustion chambers. For example, in some embodiments, heat pipes can be configured within combustion chamber liners, bulk heads, heat shields, swirlers, hoods, support shells, etc. Thus, the present disclosure is not intended to be limited to only fuel injectors.

Moreover, although shown and described with respect to an aircraft engine, those of skill in the art will appreciate that embodiments provided herein can be employed within land-based or sea-based gas turbine engines and/or so industrial gas turbines (IGT). Furthermore, combustors as provided herein can be annular combustors, can combustors, or other types of combustors as known in the art. Further, in some embodiments, such as in industrial gas turbines, as known, water may be injected into the combustion chamber and used for emission control. Such water and/or associated water supply can be used as a cooling source for the heat pipes as described herein.

Accordingly, the present disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims

What is claimed is:

1. A fuel injector for a gas turbine engine comprising:

a nozzle configured to dispense fuel into a combustor of a gas turbine engine;

a fuel conduit fluidly connecting a fuel source to the nozzle; and

a heat pipe having a vaporization section and a condensation section, wherein the vaporization section is in thermal communication with the nozzle and the condensation section is in thermal communication with a cooling source of the gas turbine engine.

2. The fuel injector ofclaim 1, wherein the cooling source is at least one of the fuel of the fuel injector, compressed air, or water.

3. The fuel injector ofclaim 1, wherein the vaporization section of the heat pipe is wrapped around the nozzle.

4. The fuel injector ofclaim 1, wherein at least a portion of the heat pipe passes through a wall of a portion of the fuel injector.

5. The fuel injector ofclaim 1, wherein the heat pipe is integrally formed with at least one of the nozzle and the fuel conduit.

6. The fuel injector ofclaim 1, wherein the heat pipe is one of a thermosiphon, a capillary-driven heat pipe, an annular heat pipe, a vapor chamber, a gas-loaded heat pipe, a loop heat pipe, a capillary pumped loop heat pipe, a pulsating heat pipe, a micro heat pipe, or a miniature heat pipe.

7. The fuel injector ofclaim 1, wherein the nozzle and fuel conduit are components of an axially staged fuel injector.

8. The fuel injector ofclaim 1, wherein the nozzle and fuel conduit are components of a radially staged fuel injector.

9. The fuel injector ofclaim 1, wherein at least a portion of the fuel injector is additively manufactured and the heat pipe is formed by the additive manufacturing process within the fuel injector.

10. The fuel injector ofclaim 1, wherein the heat pipe is a pulsating heat pipe.

11. A gas turbine engine comprising:

a combustor section having a plurality of components; and

a heat pipe configured with at least one of the plurality of components of the combustor section, the heat pipe having a vaporization section and a condensation section, wherein the vaporization section of the heat pipe is in thermal communication with the at least one component and the condensation section is in thermal communication with a cooling source.

12. The gas turbine engine ofclaim 11, wherein the at least one component is a first fuel injector having a nozzle and a fuel conduit fluidly connecting a fuel source to the nozzle, wherein the vaporization section is in thermal communication with the nozzle and the condensation section is in thermal communication with the cooling source.

13. The gas turbine engine ofclaim 12, wherein the vaporization section of the heat pipe is wrapped around the nozzle.

14. The gas turbine engine ofclaim 12, wherein the nozzle and fuel conduit are components of an axially staged fuel injector.

15. The gas turbine engine ofclaim 12, further comprising a second fuel injector that is a radially staged fuel injector of the gas turbine engine.

16. The gas turbine engine ofclaim 15, wherein the second fuel injector includes a second nozzle configured to dispense fuel into the combustor and a second fuel conduit fluidly connecting a second fluid source to the second nozzle, the gas turbine engine further comprising a second heat pipe having a vaporization section and a condensation section, wherein the vaporization section of the second heat pipe is in thermal communication with the nozzle of the second fuel injector and the condensation section of the second heat pipe is in thermal communication with a second cooling source.

17. The gas turbine engine ofclaim 16, wherein at least one of the first and second fluid sources are the same fluid source or the first and second cooling sources are the same cooling source.

18. The gas turbine engine ofclaim 11, wherein the heat pipe is integrally formed with the at least one component of the combustor.

19. The gas turbine engine ofclaim 11, wherein the heat pipe is one of a thermosiphon, a capillary-driven heat pipe, an annular heat pipe, a vapor chamber, a gas-loaded heat pipe, a loop heat pipe, a capillary pumped loop heat pipe, a pulsating heat pipe, a micro heat pipe, or a miniature heat pipe.

20. The gas turbine engine ofclaim 11, wherein the component of the combustor is additively manufactured and the heat pipe is formed by the additive manufacturing process within the component.